Bug 17308 - 'New patron attribute type' button does not work

Bug 17308 - 'New patron attribute type' button does not work

In the Staff client, the 'New patron attribute type' button in the Patron
attribute types page does not work. This patch fixes that.

Test plan:
1) In the Staff client, go to Home > Administration > Patron attribute types,
   and click on the 'New patron attribute type' button. You cannot create a
   new patron attribute type and you get the following Software error:
   Not a HASH reference at [...]
2) Apply the patch.
3) Repeat step 1). The 'New patron attribute type' button now works.

Followed test plan, works as expected.
Signed-off-by: Marc Véron <veron@veron.ch>
Signed-off-by: Katrin Fischer  <katrin.fischer@bsz-bw.de>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>